OpnForm vs Tasks.org CalDAV Sync
A side-by-side comparison of two self-hosted calendar & contacts options — licensing, setup difficulty, resource needs, and what each one replaces.
Not the right match-up?
OpnForm
Beautiful open-source form builder
VS
Tasks.org CalDAV Sync
Open-source calendar and task sync client for Android
| Feature | OpnForm | Tasks.org CalDAV Sync |
|---|---|---|
| Category | Calendar & Contacts | Calendar & Contacts |
| License | AGPL-3.0 | GPL-3.0 |
| Language | PHP | Kotlin |
| Setup difficulty | Medium | Easy |
| Min. RAM | 512 MB | 128 MB |
| Deployment | docker | binary, source |
| GitHub stars | ★ 3,545 | ★ 2,784 |
| First released | 2026 | 2013 |
| Replaces | — | Google Calendar Sync, iCloud sync |
Why pick each one
Choose OpnForm if…
- Released under the AGPL-3.0 license
- First-class Docker support for quick deployment
- Active community (3.5k GitHub stars)
- Written in PHP
Choose Tasks.org CalDAV Sync if…
- Released under the GPL-3.0 license
- Easy to set up — beginner-friendly
- Active community (2.8k GitHub stars)
- Written in Kotlin
Frequently asked questions
Is OpnForm or Tasks.org CalDAV Sync better?
Neither is universally better. OpnForm has the larger community, while Tasks.org CalDAV Sync is simpler to set up (easy difficulty). Choose based on the comparison table above and your own setup.
Are OpnForm and Tasks.org CalDAV Sync free and open-source?
Yes. OpnForm is licensed under AGPL-3.0 and Tasks.org CalDAV Sync under GPL-3.0. Both can be self-hosted at no software cost.
Can I run OpnForm and Tasks.org CalDAV Sync with Docker?
OpnForm: yes. Tasks.org CalDAV Sync: check the project docs for container support.